In a navigation system, for example, when various conditions are inputted, a list of facilities which fulfill the conditions is displayed. In cases where such a system is provided with a plurality of databases, when common input data is inputted to a plurality of databases to search for facilities and when the databases provided are different, the output results may be different mutually. This is because the contents of the database are dependent on an information network of a contents provider (facility manager) who manages the database, and because the output results in the present case are different in spite of the same facility. This kind of related art is disclosed by Patent Document 1.
According to technology disclosed by Patent Document 1, facilities are searched for using a facility database stored in a DVD in a navigation device, and the facilities are searched for also using a facility database of an information center by transmitting a search word to the information center. Then, the results of these searches are compared. When the position of a facility searched in the navigation device and the position of a facility searched in the information center are within a predetermined range, both facilities are regarded as the same facility and the information on the facility retrieved from the facility database of the DVD is deleted, and either of the these items of facility information is displayed on the display unit.